U.S. President George Bush this week asked Congress to renew an international program for HIV/AIDS prevention and treatment, and to double the funding to $30 billion over the next five years.

Speaking outside the White House, he said the money will be spent in joint arrangements called partnership compacts.

BUSH: "America will work with governments, the private sector, and faith- and community-based organizations around the world to meet measurable goals, support treatment for nearly 2.5 million people, to prevent more than 12 million new infections, and to support care for 12 million people, including more than 5 million orphans and vulnerable children."

President Bush on Wednesday.

Africa is, of course, the continent that has suffered most from the HIV/AIDS epidemic. It is also a region where armed conflict has frequently raged in some of the areas hardest-hit with AIDS. Now, a study published this week suggests that HIV prevention and treatment programs can be effective, even in conflict zones.

Many health care providers have traditionally felt it wasn't worth it to try to sustain AIDS treatments in war zones. If the course of treatment is interrupted, patients can develop resistance to medication.

But the humanitarian organization Doctors Without Borders found that they could continue HIV treatment even in the conflict-ridden Democratic Republic of the Congo. Daniel O'Brien, the HIV/AIDS advisor to the group's office in Amsterdam and co-author of the new report, says giving AIDS care in such an environment requires proper planning, resources and flexibility.

O'BRIEN: "There are significant benefits for the patients involved. But the program does need to be set up and have in mind, I guess, the potential that the program could be disrupted by conflict, and to try and increase the chances that it'll be sustainable should that happen, but also reduce the risks to the patients on therapy should they have to interrupt [their treatment]."

The study focuses on Bukavu, a mid-sized Congolese city where Doctors Without Borders has had an AIDS program since 2000. Although Bukavu was generally spared the worst of the decade-long fighting in the region, it flared up in the summer of 2004, when rebels invaded the city.

The situation called for flexibility. During the crisis, nurses dispensed medication from home instead of the clinic, for example, and patients were informed of the new arrangements by both word-of-mouth and radio broadcasts.

Doing medical work in conflict zones has obvious risks and challenges, but Daniel O'Brien and his colleagues from Doctors Without Borders say that's no reason not to do it.

O'BRIEN: "If you have to guarantee that a program will always continue and will always be stable, then in most parts of these conflict-affected areas you'd never do anything and then you'd have large numbers of people needing care who would never access it."

In their paper, O'Brien and his colleagues conclude that there are a number of things that can be done to ensure a continuity of care: Educate patients on the importance of not interrupting treatment. Cross-train staff to fill gaps that can occur in emergencies. And provide medical records to patients in case they have to continue their treatment elsewhere, among others.

Dr. O'Brien's study was published in the journal PLoS Medicine.

Physicians more than a century ago described a disorder they called the "wild-child syndrome," a reference to the documented case of a boy who could not, or would not, speak and who some believed had been raised in the wilderness by animals. Today, the disorder now known as autism will develop in approximately one in 150 newborns in the United States before they reach the age of three, according to the U.S. Centers for Disease Control. Modern medicine is still searching for the underlying neurological causes and the best methods of treatment. VOA's Andrew Baroch looks at one parent's mission to find the answers, to help improve the life of his autistic son.

BAROCH: The word autism was coined by a medical researcher about a century ago to describe an unusual childhood disorder, meaning:

CONLON: 'Self-directed. Internally-driven. Set off [from people] by one's self.'

BAROCH: Dr. Chuck Conlon, an expert on autism and a pediatrician at the Children's National Medical Center in Washington, D.C., says physicians today use the term autism as shorthand for a broader, complex set of disorders. The symptoms, Conlon says, are identifiable by the age of three, mild to severe: autistic children may say very little, refuse eye contact or other interaction with their families, and many make involuntary movements such as hand flapping and other repetitive movements.

Dr. Conlon says that at its core, the autism spectrum is a neuro-biological disorder that evolves during the first three years of a child's life.

CONLON: "Clearly, we know over the years, this is a neuro-biological disorder; it is brain-based. We're trying to understand where the brain changes and how this evolves."

BAROCH: Evolving in recent years in response to this disorder has been a grassroots movement among parents of autistic children and autistic individuals themselves, which advocates that people with autism be treated with more dignity and hopefulness and not, as many activists allege, solely as subjects for clinical examination.

BAROCH: Ralph Savarese is the author of Reasonable People: a Memoir of Autism and Adoption, a story that chronicles the dramatic improvements in the language and behavior skills of his autistic son D.J. Savarese and his wife adopted D.J. when he was six years old; he's now 15.

SAVARESE: "He's still autistic. He has bad days. But we have gotten the kid into a regular school. He has friends, he has a little girlfriend. He's your regular adolescent in many, many respects."

BAROCH: Savarese and his wife Emily treated D.J. by teaching him literacy skills through typing on a computer. But Dr. Conlon of the Children's National Medical Center warns of raising expectations too high:

CONLON: "We're always hopeful, for those of us who work in the field, that when we see a young child at two or two and a half, that they're going to be one of the children who was written [about] in this book. But I think it's also important that we don't give false hopes to all families of children with autism."

BAROCH: Conlon says parent-child interaction through pictures or games are effective interventions. But he says Savarese's approach, called Facilitated Communication, where the parent or other assistant helps the child type new words, is neither a new idea nor a panacea.

CONLON: "Facilitated communication was one of those things that was very, very well-studied many years ago and found in general not to be a very helpful intervention for most children."

BAROCH: Whatever the value of the therapy, author Ralph Savarese says he is one of a growing number of parents of autistic children and autistic adults seeking more acceptance and respect from society — the way they are.

SAVARESE: "I think this is a new movement, but it's gaining ground especially as more and more people with autism are given opportunities to educate themselves, to become communicative so that they can talk back to the empire of science."

BAROCH: As advocates seek to ensure greater public acceptance of autistic individuals as part of the human family, scientific efforts continue to shed new light on this medical mystery. The National Institutes of Health is embarking on a major new study of 100,000 pregnant women all over the country, with the mission of studying their newborns to the age of 21 and examining all the factors that may contribute to this profoundly disturbing and puzzling disorder. I'm Andrew Baroch.

According to the World Health Organization, there have been just over 300 known human cases of avian, or bird flu. But the disease has killed more than half of those have become infected. Scientists warn that it's possible the flu virus could mutate in a way that would make it spread easily from person-to-person — something it doesn't do now. In that case, it could turn out to be the world's next health emergency. Researchers aren't waiting for that to happen, however, and as we hear from health reporter Rose Hoban, a novel treatment is showing promise.

HOBAN: For the past decade, scientists have been monitoring with alarm the slow spread of H5N1 influenza around the world. Many fear that this particularly lethal form of flu — known as bird or avian flu — could become the next worldwide pandemic, resulting in millions of deaths.

Researchers are working on possible vaccines. But this week, an international group of medical scientists published a study showing that antibodies extracted from the blood of people who have already recovered from H5N1 flu could be used for treatment. Dr. Kanta Subbarao is from the U.S. National Institute of Allergy and Infectious Diseases.

SUBBARAO: "This approach of trying to generate antibodies that could then be administered to somebody is a method that's referred to as passive immunization. That's different from vaccinating somebody with a dose of vaccine and having the person make antibodies to the vaccine that then protect them from the infection. So that's active immunization. The approach we're talking about here is passive immunization."

HOBAN: Passive immunization has been used in treatments for other viral diseases — for example, rabies, chicken pox and hepatitis A. Scientists take antibodies against a disease and clone them, creating monoclonal antibodies. Subbarao says her team gave human monoclonal antibodies to mice and then proceeded to infect the mice with the bird flu virus. The mice resisted getting the flu, and when they did get sick, they didn't get as sick as mice that had not gotten the antibodies. Then, Subbarao says, they wanted to see if the antibodies could be a treatment for mice already infected with H5N1.

SUBBARAO: "We infected the mice and the next day we gave them the monoclonal antibodies, or we delayed the administration of the monoclonal antibodies up to 48 or 72 hours after infection, and we found the antibodies gave complete protection from lethality even when they administered at 72 hours post infection."

HOBAN: The antibodies Subbarao's team used were from a virus circulating in 2004. She says they worried that virus strains had changed since then.

SUBBARAO: "The good news was that some of these antibodies worked even against strains that had appeared after 2004."

HOBAN: Subbarao says this approach could be an important therapy for people who become ill with H5N1, especially in the absence of a vaccine against the disease. She says the next step will be to test the antibodies in other animals and begin testing them in humans. Subbarao's study is being published in the open-access on-line journal, Public Library of Science: Medicine. I'm Rose Hoban.

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

This week it's a very modern-looking site covering thousands of years of the history of chemistry, with a special focus on the people who have contributed so much in this modern world of ours.

GEEHR: "The Chemical Heritage Foundation's website is dedicated to preserving and sharing the history of chemistry for the general public, for practicing chemists, and for people in the chemical and molecular sciences in general."

Shelley Geehr is director of communications for the Chemical Heritage Foundation, online at chemheritage.org.

The site is a place to explore chemistry in the ancient world — from beer making to copper smelting — or learn about how chemistry is part of the fight against disease.

There are a number of online exhibits. One I liked is called "Her Lab in Your Life," about the contributions made by women in chemistry, from biochemist Gladys Emerson, who first isolated vitamin E, to the person behind the lifesaving stuff of bulletproof vests.

GEEHR: "Stephanie Kwolek is featured. She is the person who developed Kevlar. Now, that may not be something that is part of your life, but I bet that there are a lot of police out there who make it an everyday part of their life."

There's also a big section on the ChemHeritage site for students and teachers called, logically enough, Classroom Resources.

GEEHR: "We have Chemical Achievers, which is a wonderful collection of very brief bios, lots of images, lots of detail. And then we have Pharmaceutical Achievers, which gives, actually, classroom activities that you can do, including how to make aspirin."Q: How to make aspirin in the classroom?GEEHR: "Yes!"Q: Wow.GEEHR: "So we have a range of things for teachers and students. You can learn a lot."

Lots to learn about chemistry from the Chemical Heritage website at chemheritage.org, or get the link from our site, voanews.com/ourworld.

It's about time we dug into the Our World mailbag to answer a listener question, and we've got a great one from Mr. Emmanuel Asogwa, writing from Nigeria. He asks, simply, "what is antimatter?"

For the answer we turned to Helen Quinn, physics professor at the Stanford Linear Accelerator Center in California, where they actually create and study antimatter. Dr. Quinn says antimatter particles are kind of an electrical mirror-image of their regular matter counterparts.

QUINN: "There are, in fact, particles that are just like each particle except with charges reversed. So we know about an electron, it has a negative electric charge. There's a particle with exactly the same mass that has a positive electric charge. For the proton there's an antiproton. For the neutron there's an antineutron. Now first you might ask, well if it's opposite charge, what's the difference between a neutron and an antineutron. But today we know neutrons and protons are made up of things called quarks, and when you look at an antineutron, it's made of antiquarks with opposite charges."

When the universe was formed billions of years ago, in theory, there should have been equal amounts of matter and antimatter, but in fact there was a very slight excess of matter. Scientists are not sure why, but it's a good thing, since when matter and antimatter come together, they annihilate each other.

QUINN: "So if matter and antimatter had stayed equal, today there'd be none of either left, and the universe would be a very empty place, and we would not be here."

Scientists like Helen Quinn can make antimatter particles in powerful "atom smashers" like the Stanford Linear Accelerator, where she studies them. But what about the antimatter of science fiction, where it's used as an energy source?

In theory, or on the star ship Enterprise of TV's Star Trek series, there may be something to it, but Quinn says it bogs down in issues of engineering and efficiency.

QUINN: "Of course, it's very expensive to make that fuel, and nobody knows how to contain it. So the idea at first blush is not crazy, but as soon as you start trying to think of a practical version of it, it becomes very impractical very quickly."

Science fiction writers have also deployed antimatter weapons, but some of the same practical issues apply, and in any event, the world probably has enough weapons already.

Thanks to Emmanuel Asogwa for asking about antimatter. We'll be sending him a special VOA gift in appreciation for his excellent question. If you've got a science question, please send it in. Our email address is ourworld@voanews.com, or listen for our postal address at the end of the show.

Scientists are seeking new ways to reverse the build-up of carbon dioxide in the atmosphere, which is generally accepted by scientists as a cause of global warming. VOA's Brian Wagner reports one U.S. project aimed at stimulating plankton growth in the oceans is raising some debate about its possible effectiveness.

WAGNER: Environmental groups have long advocated planting trees as one way to reverse the build-up of carbon dioxide in the atmosphere. Trees absorb small amounts of carbon dioxide to survive. Marine scientists say that growing tiny organisms in the ocean known as plankton also can help cut carbon dioxide levels in the atmosphere.

The U.S. firm Planktos is planning to revive plankton in several regions of the Pacific Ocean as an effective way to absorb atmospheric CO2 and counter global warming. Planktos climate expert Melodie Grubbs says iron is the key nutrient needed to stimulate plankton growth.

GRUBBS: "Once we put that in, iron acts as a catalyst for photosynthesis, which creates plankton. It's a missing nutrient in the ocean, and from that sparks a natural plankton bloom."

WAGNER: Researchers say plankton blooms are down because less iron dust is being blown onto the ocean's surface by nutrient-rich winds. Planktos says dust supply has fallen 30 per cent over the past 30 years, resulting in a 10 per cent decline in plankton populations. The Planktos team hopes to reverse the trend by seeding the waters off the Galapagos Islands and several other spots in the Pacific Ocean.

Researchers have been studying the effects of iron seeding on carbon dioxide levels in the atmosphere for more than two decades. Frank Millero, professor of marine chemistry at the University of Miami, helped pioneer some of the techniques in the 1990s.

MILLERO: "Even at that time people were thinking about this as a solution. We were more interested in showing that (lack of) iron was limiting to plant growth."

WAGNER: The Planktos team says it is building on the research of Millero and other scientists. But unlike academics, the California firm hopes to get financing from major companies that release carbon dioxide into the atmosphere. The companies would compensate Planktos for reducing greenhouse gas emissions globally, without altering their own manufacturing process.

Planktos says it hopes to sell these so-called carbon credits or offsets. Profits from the sales will create new opportunities for environmental restoration, says Planktos project manager Michael Bailey.

BAILEY: "We are part of the international carbon credit community, part of that marketing plan, basically trying to find a way to make money by restoring the oceans and the earth's atmosphere. So this is a beautiful business model."

WAGNER: Experts, however, disagree on how much carbon dioxide is absorbed by plankton blooms, which tend to last no more than two or three weeks. Professor Millero says a key concern is whether plankton seeded with iron can have a long-term effect.

MILLERO "The problem, if there is one, is if the carbon dioxide in the plant material does not sink to the deep waters and become oxidized there, then the net effect is not as large as you might hope for."

WAGNER: Scientists say plankton has a positive impact on global warming only when carbon-based material in it sinks to deep waters, where it can remain for centuries. Often, some of the material remains near the water's surface, where it is broken down and released back into the atmosphere as carbon dioxide.

Another concern is whether iron seeding can produce more plankton blooms than those that occur naturally.

David Archer is a professor of geophysical science at the University of Chicago.

ARCHER: "Fertilizing the ocean, it is not at all clear there is any effect on CO2 in the atmosphere. In models of the oceans, if you fertilize the ocean here, and reduce the fertility of the ocean somewhere else, the net effect globally will be very small."

WAGNER: Experts may not agree on the best method to fight greenhouse gas emissions, but they do agree that lowering emissions from fossil fuels alone is not enough. Many say the world needs to find techniques to reverse decades of emissions and pull carbon dioxide from the atmosphere. Brian Wagner, VOA News, Miami.

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That's our show for this week. We're always interested in your comments or your science questions. Email us at ourworld@voanews.com. Or use the postal address —

Our World Voice of America Washington, DC 20237 USA.

Rob Sivak edited the program. Eva Nenicka is the technical director. And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.